I strongly recommend Sasuga Books, a specialty store in the Boston area. They have at www.sasugabooks.com. Karen, the store manager, has been very helpful in locating Japanese martial arts books which are not in their extensive stock. She even fixed me up with a subscription to Kodokan Judo Magazine for six months during their last Olympic coverage. IF you can't find what you're looking for in their online catalog, give them a call.